Unfathomable Titans of the Deep



Some are as big as an elephant and most are toothless. They dive deeper than any other animals on Earth to engage colossal squid in undersea battles. They are missile-shaped stealth-predators using subdued sonar and superior agility to target their prey. They are neither what we’d call ‘whales’ or ‘dolphins’; they are the the unfathomable ‘beaked whales’ and make up a quarter of all Australia’s marine mammals. 

On 2 June 2004, a call came in that a female Cuvier’s Beaked Whale had stranded at Sealers Cove, a two hour walk from the nearest road in Wilson’s Promontory National Park. Early reports were she entered the shallow bay with a calf before beaching herself. Sadly, by the time we got there she had died and the calf was nowhere to be seen. 

Most of what we know about beaked whales comes from studying stranded animals but to understand enough of the significance and behaviour of these enigmas is almost impossible. To put this in perspective, Shepherd’s Beaked Whale, one of the few that has teeth, was only described in 1937 from the Taranaki coast of New Zealand. As of 2006, there had been about 42 strandings.  

Here's an extract from a trip report about The Mysterious Shepherd’s Beaked Whale:

When Mark Cawardine (of the BBC series 'Last Chance to See' fame, with Stephen Fry) published The Eyewitness Guide to Whales, Dolphins and Porpoises in 1995, Shepherd's Beaked Whale was illustrated mostly as an artist’s impression. At that time, there had been no definite sightings at sea and the only markings on beached animals tended to be obscured, as skin pigment darkened in the sun.  Unknown to them and just when they were preparing for print, a freshly dead animal was hauled onto shore by scientists at Te Papa Museum in Wellington, New Zealand.  This was the first time the true identity of this obscure whale was known.   

In the last few years, there have been a small handful of sightings at sea. 

Longman’s or ‘Tropical’ Beaked Whale was first described in 1926 by Heber Longman, from a single skull found at Mackay in 1822. The tradition of naming beaked whales after taxonomists reveals how little we ever expect to know about them, even what they look like. A fresh carcass in the year 2000 and new DNA techniques have now enabled the re-labelling of skeletons recovered between the Indian and Pacific Ocean, from the coasts of South Africa to Japan. There are now photos of Longman’s at sea, we know roughly where to find them - it took nearly 200 years to solve the puzzle. We still don’t have any decent documented sightings off Australia. 

Until recently, all that was known about Spade-toothed Beaked Whale was from three partial skull fragments found in 1872 (it was given this banal name because the describing taxonomists already had beaked whales named after them, though the scientific name traversii was in honour of the original collector). It was not until 2010 that a mother and calf stranded alive on New Zealand’s North Island. Both died and once again DNA enabled the mystery to be solved. No-one has ever seen one at sea.

And so, the list goes on ... True’s Beaked Whale, Gingko-toothed Beaked Whale, Hector’s Beaked Whale, Andrew’s Beaked Whale ... species after species, we know almost nothing about them, yet as a group they appear to be widespread and probably not uncommon. There are almost certainly new beaked whales to be discovered, possibly even in Australia.

Worldwide, the most recent discoveries include Perrin’s Beaked Whale, which was described from the Californian coastline in 2002.  In 2016, a new, 7-8m long beaked whale was described in Alaska, after one was found dead on a beach.  

The Cuvier’s Beaked Whale that died at Wilson’s Promontory is one of the more common throughout the world and is reasonably well-studied. In 2006, scientists in Hawaii were able to fire suction cups with recording devices onto their backs to track them swimming. This revealed the deepest dive of any marine mammal ever ... nearly 2,000m. At this depth, the pressure per square inch on their body is incredible, equivalent to industrial car-crushers. 

During aerial surveys over the Bass Canyon, 200km east of Wilson’s Promontory, we once saw a Cuvier’s Beaked Whale flanked by a pod of Common Dolphins. It’s quite likely this animal made her way along the coastline, searching for a sheltered bay. One can imagine the exhaustion suffered by a less than healthy mother whale with a newborn in tow.  

The most convincing argument for why whales ‘strand’ was explained to us once by a marine biologist from San Diego who for a while, had worked as second mate on ‘The Odyssey’, a steel sailing vessel circumnavigating the world doing research on Sperm Whales. 

He said: “You know whales have to make the choice to breath don’t you? They aren’t like us, we breath without thinking but whales can’t afford to do that. They have to stop and make a conscious decision when they surface”. He went on ... “The most terrifying thing that could ever happen to you if you are a whale or dolphin has to be drowning”. 

Water surrounds every aspect of a whale or dolphin’s daily life and they would be patently aware of the capacity to drown in it. Becoming too weak to swim, they would start fearing for their own life, consumed with the terrifying reality that unless they can stay upright, their own environment is going to kill them. The first thing they do is look for sheltered water. The last resort - stranding - is the only way to avoid the inevitable. 

Our Cuvier’s Beaked Whale must have found herself in difficulty fairly quickly, possibly as a result of giving birth. She was otherwise fit and healthy and had a stomach packed still full of squid beaks. 

Mark Norman, a squid expert and scientist from Museum Victoria, did a preliminary assessment confirming that two of the beaks were from the fearsome-looking and utterly unique Vampire Squid. These typically occur at depths of 600-1,200m but are only about 13cm long. The very large beaks, several centimetres across were from glass squid, a diverse group that includes some of the biggest in the world, including Colossal Squid (Mesonychoteuthis). To think that just days before, our mother may have been grappling in a fight to the death with another of the world’s most elusive and mythical animals.  

Examination of Colossal Squid off New Zealand have found 4.2cm beaks from animals weighing almost half a tonne and several metres long. Beaked Whales are often covered in marks and scars, some of which are from ravenous cookie-cutter sharks, but others perhaps inflicted by razor-sharp teeth on the suckers that line the squids’ tentacles.   

The fact is beaked whales are common but they feed all day, surface briefly showing only a tiny fraction of their back and dorsal fin, live 30 miles offshore and actively avoid boats. 

I’ve spotted them numerous times on day trips off Australia’s east coast, though often identified merely as ‘beaked whale’ on a momentary sighting. We once saw what appeared to be Gray’s Beaked Whales while crossing the Great Australian Bight and I’ve seen possible Cuvier’s and Blainville’s Beaked Whales off Scott Reef in the Kimberley.   

In the last two years, there have been four sightings at sea of Shepherd’s Beaked Whale off the Victorian coastline (this is now the world epicentre of sightings) and we’ve had Strap-toothed Beaked Whales strand nearby - so-called because of the flat teeth that grow from the base of the males’ jaws. These two functionless teeth overlap and bizarrely, restrict the mouth opening (presumably meaning they feed partially using suction).

As we extend oil and gas and naval activity ever further offshore, we come into greater contact with these extraordinary animals. Yet despite investment in technology to study them, our knowledge of most species is primitive to say the least. We have no more than a handful of sightings at sea for any of the 12 species that occur off Australia. We don’t even know where they are  ... there’s never been a survey of marine wildlife, even seabirds, done around our coast.  

Two hundred years ago, we inferred wisdom about beaked whales based on studies of skull morphology, these days we may be able to do DNA analysis and look at stomach contents but we’re still resigned to studying them ‘out of water’ and they perplex us greatly.  

 

We’ve not come far in the last 200 years: hardly anyone has ever heard of them, scientists know virtually nothing about them, yet they live in apparent abundance around our coastline. Australasia has a greater diversity of these enigmatic animals than anywhere else in the world. 

Wildiaries • February 2017